1. Field of the Invention
This invention generally relates to a magnetic reproducing apparatus. This invention particularly relates to a VTR (video tape recorder) of a helical scan type which can implement variable speed playback.
2. Description of the Related Art
In some home-use VTR's (video tape recorders), slow-motion playback is implemented by intermittently feeding a magnetic tape. The upper limit of the speed of the intermittent feed of the magnetic tape is determined by factors such as the moment of inertia of the capstan motor and the response characteristic of the tape feeding mechanism. Accordingly, the speed of the slow-motion playback is generally limited to within a range equal to or lower than about one-fourth of the standard playback speed (the normal playback speed). It tends to be difficult to provide a slow-motion playback speed equal to one-third of the standard playback speed or a half of the standard playback speed.
Generally, business-use VTR's are able to implement special playback in addition to standard playback (normal playback). An example of the special playback is slow-motion playback.
There is a business-use VTR having a rotary drum containing an actuator using a bimorph cell. The actuator serves to control the heights of heads supported on the rotary drum. During the special playback mode of operation of the business-use VTR, a magnetic tape remains fed continuously in synchronism with rotation of the rotary drum while the heights of the heads are controlled by the actuator to generate a reproduced signal with a constant level.